#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
const int nmax=100005;
struct thing
{
int ss,x,y;
}v[nmax];
long long p[nmax],s[nmax];
long long ans,fx;
int norm[2*nmax];
char wh1,wh2;
int n,i,j,nrr,cate,k,p1,p2;
bool comp(thing unu,thing doi)
{
return (unu.ss<doi.ss);
}
struct aibul_smecher
{
long long aib[2*nmax];
inline int lbit(int x)
{
return ((x^(x-1))&x);
}
void update(int poz,long long val)
{
for(int idx=poz;idx<=2*n;idx+=lbit(idx))
aib[idx]+=val;
}
long long compute(int poz)
{
long long ret=0;
for(int idx=poz;idx>0;idx-=lbit(idx))
ret+=aib[idx];
return ret; //:*
}
int find_kth(int k)
{
int ret=0,act=0;
for(int p=17;p>=0;p--)
if(ret+(1<<p)<=2*n&&act+aib[ret+(1<<p)]<k)
{
ret+=(1<<p);
act+=aib[ret];
}
ret++;
return ret;
}
void clr()
{
for(int idx=1;idx<=2*n;idx++)
aib[idx]=0;
}
}nr,sum;
int cb(int val)
{
int ret=0;
for(int p=17;p>=0;p--)
if(ret+(1<<p)<=nrr&&norm[ret+(1<<p)]<=val)
ret+=(1<<p);
return ret;
}
void ins(int val)
{
int poz=cb(val);
nr.update(poz,1);
sum.update(poz,val);
}
long long calc(long long x)
{
int poz=nr.find_kth(x);
long long act=norm[poz];
return (act*nr.compute(poz)-2*sum.compute(poz)+1LL*sum.compute(2*n)-act*(nr.compute(2*n)-nr.compute(poz)));
}
void solve()
{
for(i=1;i<=cate;i++)
{
ins(v[i].x);
ins(v[i].y);
p[i]=calc(i);
}
sum.clr();nr.clr();
ans=p[cate];
for(i=cate;i>=1;i--)
{
ins(v[i].x);
ins(v[i].y);
s[i]=calc((cate-i+1));
if(p[i-1]+s[i]<ans)
ans=1LL*p[i-1]+s[i];
}
}
int main()
{
//freopen("data.in","r",stdin);
ios_base::sync_with_stdio(false);
cin>>k>>n;
for(i=1;i<=n;i++)
{
cin>>wh1>>p1>>wh2>>p2;
if(p1>p2) swap(p1,p2);
if(wh1!=wh2)
{
v[++cate]={p1+p2,p1,p2};
norm[++nrr]=p1;norm[++nrr]=p2;
}
else fx+=(1LL*(p2-p1));
}
sort(v+1,v+cate+1,comp);
sort(norm+1,norm+nrr+1);
solve();
if(k==1)
ans=p[cate];
ans+=1LL*cate;
cout<<ans+fx;
return 0;
}
